Lax forms of the qq-Painlev\'e equations

All $q$-Painlev\'e equations which are obtained from the $q$-analog of the sixth Painlev\'e equation are expressed in a Lax formalism. They are characterized by the data of the associated linear $q$-difference equations. The degeneration pattern from the $q$-Painlev\'e equation of type $A_2$ is also presented.Comment: 24 page

Proton-induced magnetic order in carbon: SQUID measurements

In this work we have studied systematically the changes in the magnetic behavior of highly oriented pyrolytic graphite (HOPG) samples after proton irradiation in the MeV energy range. Superconducting quantum interferometer device (SQUID) results obtained from samples with thousands of localized spots of micrometer size as well on samples irradiated with a broad beam confirm previously reported results. Both, the para- and ferromagnetic contributions depend strongly on the irradiation details. The results indicate that the magnetic moment at saturation of spots of micrometer size is of the order of $10^{-10}$ emu.Comment: Invited contribution at ICACS2006 to be published in Nucl. Instr. and Meth. B. 8 pages and 6 figure

Thermo-mechanical analysis of dental silicone polymers

Soft lining materials are used to replace the inner surface of a conventional complete denture, especially for weak elderly patients, with delicate health who cannot tolerate the hard acrylic denture base. Most of these patients have fragile supporting mucosa, excessive residual ridge resorption, particularly on the mandibular arch. The application of a soft liner to the mandibular denture allows absorbing impact forces during mastication and relieving oral mucosa. Actually, the silicone rubbers constitute the main family of commercialised soft lining materials. This study was conducted to understand the relationships between the mechanical properties and the physical structure of polysiloxanes. For this purpose, a series of polysiloxanes of various chemical compositions have been investigated. The evolution of their physical structure as a function of temperature has been followed by differential scanning calorimetry (DSC). In order to facilitate comparisons, the mechanical modulus has been analysed upon the same heating rate using dynamic mechanical analysis (DMA). Polysiloxanes actually commercialised as soft denture liners are three-dimensional networks: the flexibility of chains allows a crystalline organisation in an amorphous phase leading to the low value of the shear modulus. The dynamic mechanical analysis shows that they are used in the rubbery state. So, polysiloxanes have steady mechanical properties during physiological utilisation

First Meeting of the joint IOC-ICES Study Group on Nutrient Standards (SGONS)

A meeting of the joint IOC-ICES Study Group on Nutrient Standards (SGONS) was held in Paris, France on 23-24 March 2010. It focused on the ongoing activities of the SGONS and plans for extended international collaborations to establish global comparability of the nutrient data from the world’s ocean. Thirty two scientists and experts from 11 countries and 2 delegates from IOC attended the meeting. The discussions followed the Terms of References of SGONS established in July 2009. Development of the reference materials for nutrients in seawater (RMNS) were also discussed in collaboration with the producers. The background and history of SGONS and an international nutrients scale system INSS and the progress with the production of RMNS materials and their current availability were reported. The production of RMNS and the latest status of the RMNS production facility, current status on the certification of RMNS for nitrate, nitrite, phosphate and silicate at the National Metrology Institute of Japan were also reported. The revised nutrients analysis manual which is being undertaken by the SGONS hopefully would be completed by 1 August 2010, and it will be published on line at the Go-Ship website. Results obtained with RMNS solutions used on the P6 reoccupation cruise in 2009-2010 by SIO (Scripps Institute of Oceanography, USA) showed that considerable improvement could be made in the internal comparability of the data by referencing it to the RMNS results and related good comparability with the previous P6 cruise in 2003 by JAMSTEC when RMNS were also used. The meeting strongly endorsed the idea of a ship board workshop in 2013/14 during which major groups would carry out a full inter-comparison of all procedures including analytical methods on board a research ship. The global stability test of RMNS by ten core laboratories of SGONS which started in 2009 will continue for more two years. It also was agreed to set up an international steering committee to plan the next inter-laboratory comparison study which will extend the study to about 70 laboratories working globally on deep sea hydrography. This will happen in early 2011. Future arrangements were considered for the collection of more batches of seawater for the preparation of RMNS waters suitable for use in all major water masses, and a list of candidate cruises in 2010/2011 was prepared. The related point of the extension of the use of RMNS for work in shelf sea water was also discussed, this followed on from discussions at the ICES Marine Chemistry Working Group (MCWG) meeting in 2010. The ICES MCWG considered that the use of suitable RMNS solutions would be valuable for improving the inter comparability of shelf sea data and be a valuable complement to work with the existing QUASIMEME proficiency testing scheme

Tropical Krichever construction for the non-periodic box and ball system

A solution for an initial value problem of the box and ball system is constructed from a solution of the periodic box and ball system. The construction is done through a specific limiting process based on the theory of tropical geometry. This method gives a tropical analogue of the Krichever construction, which is an algebro-geometric method to construct exact solutions to integrable systems, for the non-periodic system.Comment: 13 pages, 1 figur

Induced Magnetic Ordering by Proton Irradiation in Graphite

We provide evidence that proton irradiation of energy 2.25 MeV on highly-oriented pyrolytic graphite samples triggers ferro- or ferrimagnetism. Measurements performed with a superconducting quantum interferometer device (SQUID) and magnetic force microscopy (MFM) reveal that the magnetic ordering is stable at room temperature.Comment: 3 Figure